<!DOCTYPE html>
<html>
<head>
	<meta charset="utf-8">
	<meta http-equiv="X-UA-Compatible" content="IE=edge">
	<title></title>
	<link rel="stylesheet" href="">
	<style type="text/css" media="screen">
	div {
		width: 600px;
		margin:0 auto;
	}
		header {
			width: 600px;
			height: 70px;
			background: red;
		}
		#div {
			display: flex;
		}
		article {
			flex: 1;
			height: 300px;
			background: blue;
			float: left;
		}
		aside {
			width: 200px;
			height: 300px;
			background: green;
			float: right;
		}
		footer {
			width: 600px;
			height: 70px;
			background: red;
		}
	</style>
</head>
<body>
	<div>
		<header>header</header><!-- /header -->
		<div id="div">
			<article>
			arcitle
		</article>
		<aside>
			aside
		</aside>
		</div>
		<footer>
			footer
		</footer>
	</div>
</body>
</html>